[968forums]

compliments of 968 Forums member <b>Johannvb</b>

Idle_Control_Valve_DIY_2.pdf Size: 394.99 KB  Downloads: 358

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[Jamie '92 968]

Thanks again Johann, and nice job on the DIY.
I can't wait to give this a go.


Here's a question to reveal my level of ignorance (again).

How do I remove the factory hose clamps, and can I re-use them after I remove them?
I'm guessing that a special tool would be needed to reinstall them if this is possible.


Jamie

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[Johannvb]

Jamie, the factory hose clamps can only be used once as far as I know. What I do to remove them is to slide a smallish flat head screw driver into the loop and then turning it. I keep upgradring to a bigger screwdriver until the clamp pops open. Be carefull not to damage you hoses though.

Maybe someone else has a better method, but this work fine for me. I replaced my clamps with a brand called ABA from Sweden. I find them to be the best quality.

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[apex]

Ha! I remove them by destroying them! Then they get replaced with a nice all-stainless-steel solid-banded clamp that I purchase from West Marine

The ABA clamps are very nice, too - didn't know about those.

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[Jamie '92 968]

Thanks for the help!
[img]style_emoticons/<#EMO_DIR#>/smile.gif[/img]
Jamie

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[Jamie '92 968]

Johann,

I've looked things over and am on my way out to buy some hose clamps and MAF cleaner.
One last question (no guarantees here [img]style_emoticons/<#EMO_DIR#>/wink.gif[/img] )
The most difficult thing about the procedure seems to be getting access to the second nut holding on the ICV clamp (the one not shown in the picture in the DIY).
Any advice on how to get to that nut?
I assume that you didn't have to move anything not described in the DIY. Did you use any sort of special tool not found in my minimal/basic tool kit to get around the corner?

Thanks again for the DIY, and for the additional help to the novice.
Jamie

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[Johannvb]

Jamie,

I used a 1/4 inch socket set, with a number 10 socket. But since there is so little room to move down there, I just loosened the nut with the socket and then did the rest by hand. If you take the socket of the ratchet you can use the socket on its own, and this will stop you from dropping the nut down the engine compartment.

Good luck!

Oh, yes....My muscles are aching today. This job is like playing twister with your car [img]style_emoticons/<#EMO_DIR#>/tongue.gif[/img]

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[sstman]

How much of an improvement to the Idle of the engine did you notice?, I was very pleased with the results, when I did the job, although it not the easiest of jobs to do on the 968, very tricky, although I did find my magnet on a telescopic rod came in very useful with those pesky little nuts! lol

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[Johannvb]

It's hard to say how much was down to the Idle Control Valve, since I also replaced the coil and temp sensor. But the Idle control valve used to buzz when the ignition was on, this lead me to believe that it was getting resistance when tyring to open up. After I cleaned the valve the buzzing is gone, so I assume it is working normally again. What I did notice is that the engine is now idling at about 1100 rpm when cold, where it used to be at around 900. When the car is warm, the idle still sits at around 800.

The idling is smoother now and the occasional hicup I used to hear is gone.

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[Jamie '92 968]

I'm done!
Thanks for all the advice and the great instructions.

Luckily I managed to make it through without dropping the nuts. I was really scared and did a short victory dance when I had them back on successfully.

In hindsight, this was not that tough of a job. The hardest part for me was getting the last hose disconnected from under the throttle body, but a firm pull finally did the trick.

OK, for the results:

The bad news is that I had every intention of making a short video clip of the tachometer before and after the job, but my camera battery was dead (and so was the back-up battery).
The good news is that the idle is definitely more steady. It used to idle around 950 +-50, and now 950 +-5 or 10 (just barely perceptible).
I also noticed that the cold idle is a bit higher now too, around 1100.

THANKS AGAIN!
[img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

Jamie

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[Johannvb]

Excellent news!

I just love working on these cars. [img]style_emoticons/<#EMO_DIR#>/wub.gif[/img]

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[Jamie '92 968]

I've been thinking about my 950 idle, vs. most others at 800...
One thing I noticed in cleaning the ICV was that the valve sat at about 3/4 closed without power (while I was cleaning it) and could be moved either more open or closed, and would spring bacl to 3/4 closed.

Is this normal operation, or could it be that the valve should nominally be closed. Could this explain my fast idle?

Johann, SSTMAN, or anybody else recall what their idle control valve looked like when you had it out of the car?

Jamie

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[Johannvb]

I have a close-up picture of the valve that will show you what you're looking for. Unfortunatey I can't upload pictures to this topic.

@admin...can you maybe add it?

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[flash]

just for the record, manual trans idle should be 840 and tip idle should be 880

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[968forums]

   

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[Jamie '92 968]

Thanks. [img]style_emoticons/<#EMO_DIR#>/smile.gif[/img]
Excellent picture.

That looks like where my valve sat.
Good thing too, since I looked up the price for a new idle control valve on Pelican and it was just over $500 !!

I'll need to do some searching to figure out how to adjust my idle down to 840 from it's curent 950.

Jamie

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[flash]

first make sure the throttle cable isn't too tight - it should be taut but not so that it pulls the throttle arm

after that, there is a screw below the arm stop, but it is adjusted from below

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[968 GUY]

Check it out with a mirror, mine looks like it is slotted. I'm going to try 1/4 ratchet with flat tip bit.

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[968 GUY]

Does the idle control valve keep surging under control, or adjust idle as the car goes from startup to op temp, or continually adjust idle? I am not clear on this.
never mind, looked it up

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[flash]

yup - slotted

the valve should control the idle by means of accommodating varying airflow - it's kind of like a "buffer zone" or a pressure valve, maintaining a constant flow rate

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